26 



lected in that State showed us perithecia with dichotomously forked 

 appendages. As so many specimens on Vaccinium all prove to be true 

 Microsphcera, that collected by Schweinitz in Pennsylvania evidently 

 was the same thing, hence the synonymy as given above. Micro- 

 sphcera Vaccinii is described as a new species in the XXIII Rep. 

 N. Y. State Mus. p. 65, but though the MS. was completed in 1870, 

 it was not printed until after the publication by Cooke & Peck in 

 Journal of Botany. 



M. elevata, Burrill, Bull. 111. St. Lab. Nat. Hist. Vol. I, No. 1, p. 58. 



Mostly epiphyllous. Mycelium abundant, persistent, frequently 

 covering the leaves for some time before the appearance of perithecia, 

 which are usually few, though occasionally abundant, 100-120 tt, re- 

 ticulations large, evident when young; apppendages 6-12, sometimes 

 more, 3-4 times as long as the diameter of the perithecium, hyaline, 

 slightly colored at base, smooth, 2-4 times dichotomous, branches short, 

 not swollen, tips at first truncate, divergent, becoming acute and re- 

 curved. Asci 4-8, ovate, about 33 x 60 fi. Sporidia 4-6, mostly 4. 



On Catalpa speciosa and C. bignonioides, not uncommon in 

 Illinois, also collected in Missouri (Demetrio), and New Jersey (Ellis). 

 Probably widely distributed. 



This sometimes involves the foliage of an entire tree, giving it a 

 gray color noticeable at some distance, and causing the leaves to fall 

 prematurely. 



M. Euphorbias, (Peck). 



Erysiphe Euphorbice, Peck, 26th Rep. N. Y. State Mus. p. 80. 

 Microsphcera Euphorbice, B. & C. Grev. IV, p. 160, 



Amphigenous. Mycelium abundant, persistent. Perithecia scat- 

 tered, abundant, usually small, 80-100 ju, but often larger (120 //), 

 texture soft, elastic, reticulations 10-15 jut, frequently obscure; append- 

 ages 15-20, very long, 5-6 or more times the diameter of the peri- 

 thecium, hyaline, often slightly tinted at base, irregularly flexuous and 

 often nodularly swollen, at first simple, then part of them bifid or 3 or 

 4 times dichotomous, branches long, lax, tips sometimes bifid, but not 

 swollen or recurved. Asci 4-8, frequently 6, pedicellate, 35-40 x 

 65 fi. Sporidia 4-6. 



On Euphorbia Preslii, E. marginata, E. corollata. 



This is a common species throughout the country east of the Rocky 

 Mountains. Easily recognized by its very long, nearly colorless ap- 

 pendages. Erysiphe Euphorbim, Peck, is evidently this same thing. 

 The name seems to have been founded upon specimens in which the 

 appendages were not branched. 



